Devices for transferring a film from a carrier tape to a substrate are often used in offices, for instance, to transfer an adhesive film or tape from a carrier tape onto paper for purposes of adhering a piece of paper to a certain place on another piece or for binding one page to another. It is common to use a hand roller for such purposes. In this manner, the user can accomplish a clean, rapid and well-localized placement of an adhesive layer. Such hand rollers, when not being used, tend to quickly collect dust and they also have problems caused by the drying of the adhesive onto the roller.
In certain known apparatus of the hand roller type, there are a windup reel (take-up reel or spent tape reel) and a feed reel built into the housing. The pressure-applying element of these devices is generally a lever which protrudes from the housing, which is swivelable within the housing and biased by a spring away from a starting position. This lever generally has on its end protruding from the housing a rather large transverse pivot on which a plastic sleeve is rotatably mounted, over which the tape coming from the feed reel is fed and thence led back into the housing to be wound up on the windup reel.
The windup reel, in such an arrangement, is generally driven by a friction wheel (clutch) by way of a gear wheel drive.
The applicator element, in the form of a lever protruding from the housing, extends within the housing past its pivot point to the other side of the housing where it engages there by way of a detent element with the teeth of a toothed gear wheel on the feed reel, so that the rotation of the feed reel is prevented when the hand roller is in the starting position (resting position).
The large transverse pivot at the end of the applicator element extends sideways beyond the applicator element lever so that if the lever is pressed against its pretensioning spring, in the direction toward the housing (i.e. upwards), the spring can yield until the extended parts of the transverse pivot hit the housing.
This known arrangement has, however, the disadvantage that the pressure-applying radius at the end of the application element is very large, so that in practical use, there is only a poorly defined detachment line of the film being applied to the substrate (such as the paper); moreover, by the use of this apparatus, it is very difficult for the user to ascertain exactly up to what point on the substrate the adhesive film has actually been applied. Moreover, the variable position of the lever which serves both as the application element and simultaneously as an arrest arm for the feed reel, results in a disadvantage, namely that the release of the feed reel is only accomplished by a rather large movement of the device, so that a relatively unskilled person could very likely have difficulties in guiding the device to perform its function.
If such a roller is held at a somewhat tilted angle, even a small tilt cannot be compensated for and the desired application of the film to the substrate can fail or be incomplete.